1. Technical Field
The present application relates to sensor apparatuses, and more particularly to a sensor apparatus integrated to an injector of an internal combustion engine in which an electrical signal is outputted responding to a physical quantity of the injector.
2. Description of the Related Art
As an example of a sensor apparatus, Japanese Patent Application Laid-Open Publication No. 2010-242574 discloses a sensor apparatus which is integrated to an injector for injecting fuel to an internal combustion engine. The sensor apparatus detects the pressure of the fuel injected to the internal combustion engine and is designed such that an electrical circuit section such as a molded integrated circuit (IC) of the sensor apparatus is integrated to a housing that is screwed to the injector-body by using a jig capable of engaging with the outer peripheral portion of the housing. In particular, the jig passes over the electrical circuit section from one end side of the axial-direction of the housing to engage with the outer peripheral portion of the housing.
However, according to conventionally-used sensor apparatus, the outer shape of the housing is necessary to be larger than that of the electrical circuit section to enable the jig to be engaged with the outer peripheral portion of the housing. As a result, because of the above-described reason, the sensor apparatus cannot be shrunk in size easily.